```html
<!DOCTYPE html>
<html lang="zh-CN">
<head>
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    <title>算法精解：反转字符串</title>
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<body class="min-h-screen">
    <!-- Hero Section -->
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        <div class="max-w-5xl mx-auto text-center">
            <div class="inline-block bg-white text-indigo-600 px-4 py-2 rounded-full text-sm font-semibold mb-6 shadow-md">
                <i class="fas fa-code mr-2"></i>算法精解
            </div>
            <h1 class="text-4xl md:text-5xl lg:text-6xl font-bold mb-6 leading-tight">反转字符串</h1>
            <p class="text-xl md:text-2xl max-w-3xl mx-auto opacity-90">双指针技术的经典应用</p>
            <div class="mt-10">
                <a href="#solution" class="bg-white text-indigo-600 font-semibold px-8 py-3 rounded-lg hover:bg-gray-100 transition duration-300 inline-flex items-center">
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        <!-- Problem Card -->
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                        <i class="fas fa-question-circle text-xl"></i>
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                    <h2 class="text-2xl font-bold text-gray-800">题目描述</h2>
                </div>
                <p class="text-gray-700 text-lg leading-relaxed">
                    编写一个函数，其作用是将输入的字符串反转并返回。
                </p>
            </div>
        </div>

        <!-- Key Concept Visualization -->
        <div class="mb-16">
            <h3 class="text-2xl font-bold text-gray-800 mb-6 flex items-center">
                <i class="fas fa-project-diagram text-indigo-500 mr-3"></i> 双指针技术图解
            </h3>
            <div class="bg-white rounded-xl shadow-lg overflow-hidden p-6">
                <div class="mermaid">
                    graph LR
                    A[左指针] --> B[交换字符]
                    C[右指针] --> B
                    B --> D[左指针右移]
                    B --> E[右指针左移]
                    D --> F[直到相遇]
                    E --> F
                </div>
            </div>
        </div>

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        <div id="solution" class="mb-16">
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                <h2 class="text-2xl font-bold text-gray-800">解题思路</h2>
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            <div class="bg-white rounded-xl shadow-lg overflow-hidden mb-8 card-hover">
                <div class="p-8">
                    <div class="mb-6">
                        <h3 class="text-xl font-semibold text-gray-800 mb-3 flex items-center">
                            <i class="fas fa-brain text-indigo-500 mr-2"></i> 核心算法
                        </h3>
                        <p class="text-gray-700 leading-relaxed">
                            使用两个指针从字符串两端向中间移动，交换字符。
                        </p>
                    </div>
                    
                    <div class="grid grid-cols-1 md:grid-cols-2 gap-6 mb-6">
                        <div class="bg-blue-50 p-5 rounded-lg">
                            <h4 class="font-semibold text-blue-700 mb-2 flex items-center">
                                <i class="fas fa-stopwatch mr-2"></i> 时间复杂度
                            </h4>
                            <p class="text-blue-800">O(n)</p>
                        </div>
                        <div class="bg-purple-50 p-5 rounded-lg">
                            <h4 class="font-semibold text-purple-700 mb-2 flex items-center">
                                <i class="fas fa-memory mr-2"></i> 空间复杂度
                            </h4>
                            <p class="text-purple-800">O(1)</p>
                        </div>
                    </div>
                    
                    <div class="mb-6">
                        <h3 class="text-xl font-semibold text-gray-800 mb-3 flex items-center">
                            <i class="fas fa-code text-indigo-500 mr-2"></i> 示例代码 (Java)
                        </h3>
                        <div class="code-block p-6 rounded-lg mt-4">
                            <pre class="text-gray-200 overflow-x-auto"><code>public void reverseString(char[] s) {
    // 初始化左指针，指向数组开始位置
    int left = 0;
    // 初始化右指针，指向数组末尾位置
    int right = s.length - 1;
    
    // 当左指针小于右指针时，继续交换
    while (left < right) {
        // 交换左右指针指向的字符
        char temp = s[left];
        s[left] = s[right];
        s[right] = temp;
        
        // 左指针向右移动
        left++;
        // 右指针向左移动
        right--;
    }
}</code></pre>
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <!-- Explanation Section -->
        <div class="bg-white rounded-xl shadow-lg overflow-hidden card-hover">
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                        <i class="fas fa-book-open text-xl"></i>
                    </div>
                    <h2 class="text-2xl font-bold text-gray-800">详细解析</h2>
                </div>
                
                <div class="drop-cap text-gray-700 text-lg leading-relaxed mb-6">
                    双指针技术是算法中非常实用的一种方法，特别适用于需要在数组或字符串中进行原地操作的问题。在本例中，我们使用一个指针从字符串的开始位置（左指针）和另一个指针从字符串的末尾位置（右指针）同时向中间移动。在每一步中，我们交换这两个指针指向的字符，直到它们在中间相遇。这种方法确保了我们只需遍历字符串一次（时间复杂度O(n)），并且不需要额外的存储空间（空间复杂度O(1)），是一种非常高效的解决方案。
                </div>
                
                <div class="grid grid-cols-1 md:grid-cols-3 gap-6 mt-8">
                    <div class="bg-indigo-50 p-5 rounded-lg">
                        <h4 class="font-semibold text-indigo-700 mb-3 flex items-center">
                            <i class="fas fa-check-circle mr-2"></i> 优点
                        </h4>
                        <ul class="text-indigo-800 space-y-2">
                            <li>高效 - 只需单次遍历</li>
                            <li>节省空间 - 原地操作</li>
                            <li>直观 - 逻辑简单清晰</li>
                        </ul>
                    </div>
                    <div class="bg-yellow-50 p-5 rounded-lg">
                        <h4 class="font-semibold text-yellow-700 mb-3 flex items-center">
                            <i class="fas fa-exclamation-triangle mr-2"></i> 注意点
                        </h4>
                        <ul class="text-yellow-800 space-y-2">
                            <li>边界条件处理</li>
                            <li>指针移动顺序</li>
                            <li>字符数组与字符串区别</li>
                        </ul>
                    </div>
                    <div class="bg-green-50 p-5 rounded-lg">
                        <h4 class="font-semibold text-green-700 mb-3 flex items-center">
                            <i class="fas fa-project-diagram mr-2"></i> 应用场景
                        </h4>
                        <ul class="text-green-800 space-y-2">
                            <li>字符串反转</li>
                            <li>回文判断</li>
                            <li>两数之和</li>
                        </ul>
                    </div>
                </div>
            </div>
        </div>
    </div>

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```